arkumish

To Change "Enviroment variable" in Windows,

  if number
    In Command Prompt: set PORT=5000
    In Power Shell: $env:PORT=5000  

  if string
    In Command Prompt: set NODE_ENV=prod
    In Power Shell: $env:NODE_ENV='prod'

arkumish

let backendHost;

const hostname = window && window.location && window.location.hostname;

if(hostname === 'localhost') {
  backendHost = 'http://localhost:5000'; //when frontend and backend are on the same server
} else if(hostname === 'yourWebsitename') { //eg markde.netlify.com
  backendHost = 'backend_server_address';  //for backend hosted on different server not same as frontend
} else{
  backendHost = '';

arkumish

To proper understand the OOP in JS, we should have proper basic understanding of following topis. For each topic there is separate file for better understanding. Follow the files as per order.

1. Object Literal
2. Constructor
3. Prototypes
4. ES6 Classes
5. ES6 SubClasses

For code output

arkumish

// In real life, you make promise for doing something. Based upon ur success and failure of ur promise, u have to don certain task.
// same way, Promises work in JS, check following example

let p = new Promise((resolve,reject)=>{
  
  let a=true;
  if(a){resolve("success")}
  else{reject("failed")}
})

arkumish

var express = require("express");
var app = express();

app.get('/app1',function(req,res) {
    res.send("Hello world From Server 1");
});

app.listen(8001);

arkumish

const nodemailer = require("nodemailer"); //install this by "npm install nodemailer"

// Step 1
let transporter = nodemailer.createTransport({
    service: 'gmail',
    auth: {
        user:  'your email id', // your gmail account
        pass: 'password' // your gmail password
    }
});

arkumish

import {Component } from '@angular/core';   
import { FormsModule } from '@angular/forms'; 

@Component({
    selector: 'courses',
    template: `
     <input type="text" [(ngModel)]="name"/>
     <h2> {{name | firstWord}}</h2>
     `
  })